IMMOBILIZATION OF [Pt2(μ-S)2(PPh3)4] ON POLYMERIC SUPPORTS BY SULFIDE ALKYLATION AND PHOSPHINE EXCHANGE REACTIONS

The immobilization of the dinuclear platinum(II) sulfido complex [Pt-2(-S)(2) (PPh3)(4)] on solid supports has been investigated. Reaction with haloalkyl functionalized polymers [Merrifield's resin (chloromethylated polystyrene), chloropropyl silica, chloropropyl controlled pore glass, and bromopropyl polysiloxane] gives complexes immobilized through alkylation of one of the sulfide ligands, forming a -thiolate ligand acting as an anchor to the polymer support, akin to well-established reactions of [Pt-2(-S)(2)(PPh3)(4)] with molecular alkylating agents. The model complex [Pt-2(-S)(-SCH2SiMe3)(PPh3)(4)]PF6 was prepared as the first molecular silicon-containing derivative of [Pt-2(-S)(2)(PPh3)(4)] and was fully characterized by NMR spectroscopy, electrospray ionization-mass spectrometry, and single-crystal X-ray diffraction. Immobilization of [Pt-2(-S)(2)(PPh3)(4)] by phosphine exchange reactions was also achieved using commercial polystyrene-grafted triphenylphosphine or a new immobilized phosphine [derived by sequential functionalization of Merrifield's resin with a polyether amine and then Ph2PCH2OH].